This application makes reference to, incorporates the same herein, and claims all benefits accruing under 35 U.S.C. xc2xa7119 from my application entitled Display Device Having Pass-through Function for Picture Signal filed with the Korean Industrial Property Office on Apr. 16, 1997 and there duly assigned Ser. No. 97-13932 by that Office.
1. Field of the Invention
The present invention relates to a display device having a pass-through function which is adapted to apply the picture signal generated from a single source to multiple display devices.
2. Discussion of Related Art
As a rule, a single-source picture signal generated by a host computer is applied to just one display device for amplification and display via a cathode ray tube (CRT). In the event that a user wishes to display this picture signal, on more the one display device, the picture signal is split and applied to a plurality of display devices. In doing so, an impedance mismatch generally occurs between the signal source output and the video input of a display device. Therefore, an external device such as a signal splitter having one input and plural outputs is conventionally used to adapt the single source to multiple displays and thereby compensate for the impedance mismatch condition so that image quality can be maintained at every video input.
Such as system, however, has some distinct drawbacks.
First, the incorporation of numerous cable connections for the simultaneous display of a single picture via plural monitors reduces reliability and increases maintenance costs. In addition, the manipulation of such externally connected auxiliary equipment is cumbersome and inconvenient and results in an unsightly system design.
Second, though the number of cable connections may be reduced by using a signal splitter having a fixed number of output ports for a given number of display, such a stipulation restricts the expansion and modification of an installed computer system. For example, with a four-way signal splitter providing four outputs to four monitors, the addition of an extra monitor would require an extra output port; however, the implementation of two such splitters (a five-way splitter being non-standard) requires loads for the three unused ports.
Third, the commercially available signal splitters typically employed are essentially passive (resistive) devices which, if strung together, have an accumulative lossy effect on the video signal for every additional monitor. Thus, signal strength may be significantly reduced, lowering the signal-to-noise ratio and deteriorating the quality of the displayed image accordingly.
It is therefore an objective of the present invention to provide a display device having a pass-through function in which an applied picture signal generated from a single source can be secondarily applied to another display device for simultaneous display.
It is another objective of the present invention to provide a display device having a pass-through function which improves system reliability and reduces maintenance costs by minimizing the number of cable connections when employing multiple such displays.
It is yet another objective of the present invention to provide a display device having a pass-through function which enables a computer system employing multiple such displays to be freely expanded or modified.
It is still yet another objective of the present invention to provide a display device having a pass-through function which improves display quality by increasing the signal-to-noise ratio in a computer system employing multiple such displays.
To achieve these and other advantages and in accordance with the purpose of the present invention, as embodied and broadly described, there is provided a display device for receiving a primary video signal generated by a host computer. The display device comprises pass-through means for outputting the primary video signal and a secondary video signal corresponding to the primary video signal.